OF THE PERUVIAN AKDES. 



15 



of the flora. Of tlie genera in my list a full half, or G3 out of 

 122 genera, are Cosmopolitan^ that is to say, are Avidely spread 

 tliroughout the Avorld, and extend to the temperate regions of 

 the northern hemisphere, including Europe; and these G3 genera 

 include 127 species or five eighths of the entire number. A small 

 number of genera, which I have designated Am^liicjean^ extend 

 to the Old World, but have a limited distribution and do not reach 

 Europe. Three genera {Tlalenia^ Castllleja^ and Muelilenhergid) 

 are common to Xorth America and to temperate Asia, and may 

 for the present purpose be reckoned under the head oi American 

 genera, common to the northern and southern parts of the conti- 

 nent. Of these, including the three above named, I reckon 19 

 genera, to which belong 25 species. I next note six genera which 

 are common to South America and the cooler extratropical regions 

 of tlie southern hemisphere, and which I designate as Anta^^ctic 

 genera. These are Calandrinia^ Accenaj Oreomt/rrJiis (or Caldasia)y 

 Calceolaria^ Ourisia^ and MuehlenhecJcia^ and are represented in 



my collection by 12 species. There reuiain the genera peculiar 

 to the Andean region, using that term in a wide sense to include 

 the highlands of Central America and Mexico, as well as those of 

 Brazil and Yenezuela. Of these, termed Andean genera, I reckon 

 27, including 32 species. It is thus apparent that, so far as 

 regards genera, the flora of the Peruvian Andes is less widely 

 separated from the rest of the woi'ld than has been commonly 

 supposed, and it is only when we come to scrutinize the species 

 that we find the local character of the vegetation strongly im- 

 pressed. In fact, very nearly five sixths of the species are 



i 



exclusively Andean, and of these, the majority appear to occupy 

 only a limited area within that region. The subjoined table will 

 exhibit more clearly the distribution of the species. 



Tahle shoicinj the relative Extension of tlie Area occupied hy 



tlie indigenous Species of tlie Rimac Yalley. 



Genera. 



No. of 

 genera. 



No. of 

 Cosmopoli- 

 tan species. 



9 



1 



No. of 



American 

 species. 



No. of 



Andean 

 species. 



Cosnionol itan 



G3 



7 



19 

 G 



27 



18 

 5 

 6 



* * h « » 



1 



100 



6 

 19 

 12 



32 



• 





Anierican 









Totals 



122 



9 



29 1 1G8 



1 





1 1 



